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2. LINE Homepage:
https://linecorp.com/zh-hant/
. Last accessed 21 Oct 2017
3. WeChat Homepage:
http://weixin.qq.com
. Last accessed 5 Aug 2017
4. WhatsApp Homepage:
https://www.whatsapp.com
. Last accessed 1 Dec 2016
5. Facebook Messenger Homepage:
https://www.messenger.com
. Last accessed 1 Apr 2016